The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Today, a wide variety of computing devices, including many portable devices, support software applications that display interactive digital maps. These software applications include special-purpose applications developed specifically to provide mapping, navigation, geographic search, etc., as well as applications configured to provide any content, such as web browsers. For convenience, all such applications are referred to below as “mapping applications.” These applications may run on laptop and tablet computers, mobile phones, car navigation systems, hand-held global positioning system (GPS) units, etc. Many of these devices are equipped with a touchscreen, a touchpad, or are otherwise configured to receive input that includes finger gestures. A user may, for example, pan across a map by swiping her finger in the desired direction, zoom in on an area by pinching two fingers together, zoom out on an area by spreading two fingers apart, etc.
In general, a mapping application can display various types of geographic data including topographical data, street data, urban transit information, and traffic data. Geographic data may be schematic or based on photography, such as satellite imagery. At certain zoom levels, a user can operate a mapping application to view a map of an urban area with street names, names of landmarks, etc. The map may include representations of buildings rendered as 2D footprints, 2.5D representations (in which an approximation of the building is rendered by extruding the shape of the building from the surface), or 3D representations, with or without textures.
The mapping application also can display information about the interiors of buildings. This information (or “indoor map data”) can include, for example, floor plans, names of occupants, locations of facilities, etc. Moreover, for multi-story buildings, indoor map data can be available for several floors. This information typically is not available for every building on the map. However, when the footprint or the external shell of the building is displayed on a map, it is not immediately apparent whether indoor map data is available for inspection.